3.
INTRODUCTION
 A SOFTWARE PLATEFORM AND OPERATING SYSTEM FOR MOBILE DEVICES,
 FULL PHONE SOFTWARE STACK INCLUDING APPLICATIONS,
 BASED ON LINUX OPERATING SYSTEM,
 DEVELOPED BY GOOGLE AND OPEN HANDSET ALLIANCES,
 100% PURE JAVA CODE,
 AN OPEN PLATEFORM FOR DEVELOPERS, USERS AND INDUSTRY.

4.
HISTORY OF ANDROID
 IN JULY, 2005, GOOGLE ACQUIRED ANDROID INC., A SMALL STARTUP COMPANY,
 STARTED AS A MOBILE SOFTWARE DEVELOPMENT COMPANY ,
 DEVELOPED A LINUX-BASED MOBILE DEVICE OS,
 ON 5TH NOVEMBER 2007, THE OPEN HANDSET ALLIANCES FOUNDED, A
CONSORTIUM OF SEVERAL COMPANIES
 FIRST RELEASED IN 2008

8.
DALVIK VIRTUAL MACHINE
 INTERPRETER OPTIMIZED FOR USE ON LOW POWERED, LOW MEMORY DEVICES
LIKE PHONES
 DOES NOT MAKE USE OF JUST IN TIME (JIT) COMPILATION TO IMPROVE THE
PERFORMANCE OF AN APPLICATION AT RUNTIME
 NOT A JAVA VIRTUAL MACHINE IT USES ITS OWN BYTECODE FORMAT CALLED
“DEX”
 ALLOWS BATTERY POWER TO BE BETTER-CONSERVED AT ALL DIFFERENT STAGES
OF EXECUTION OF AN APPLICATION
 SINCE DALVIK USES THE JAVA PROGRAMMING LANGUAGE BUT NOT THE JAVA
EXECUTION ENVIRONMENT (JVM), GOOGLE IS FREE TO DEVELOP ANDROID
WITHOUT THE NEED TO LICENSE OR OBTAIN CERTIFICATION FROM SUN
MICROSYSTEMS INC

9.
LIFE CYCLE OF ANDROID APPLICATION
ACTIVITY
STARTS
onCreate()
onStart()
onResume() onPause()
onStop()
ACTIVITY IS
RUNNING
onDestroy()
ACTIVITY IS
SHUTDOWN
onRestart()
PROCESS IS
KILLED
ANOTHER
ACTIVITY
COMES
INFRONT OF
THE ACTIVITY
THE ACTIVITY
COMES TO THE
FOREGROUND
THE
ACTIVITY IS
NO LONGER
VISIBLE
USER
NAVIGATES
BACK TO
ACTIVITY
OTHER
APPLICATION
NEED MEMORY
THE ACTIVITY
COMES TO THE
FOREGROUND

11.
CONCLUSION
 ANDROID IS OPEN TO ALL: INDUSTRY, DEVELOPERS AND USERS,
 PARTICIPATING IN MANY OF THE SUCCESSFUL OPEN SOURCE PROJECTS,
 AIMS TO BE AS EASY TO BUILD FOR AS THE WEB,
 GOOGLE ANDROID IS STEPPING INTO THE NEXT LEVEL OF MOBILE INTERNET.
ANDROID IS A TRULY OPEN, FREE DEVELOPMENT PLATFORM BASED ON LINUX
AND OPEN SOURCE. HANDSET MAKERS CAN USE AND CUSTOMIZE THE PLATFORM
WITHOUT PAYING A ROYALTY.
A COMPONENT-BASED ARCHITECTURE INSPIRED BY INTERNET MASH-UPS.
PARTS OF ONE APPLICATION CAN BE USED IN ANOTHER IN WAYS NOT ORIGINALLY
ENVISIONED BY THE DEVELOPER. CAN EVEN REPLACE BUILT-IN COMPONENTS
WITH OWN IMPROVED VERSIONS. THIS WILL UNLEASH A NEW ROUND OF
CREATIVITY IN THE MOBILE SPACE.